As an important oil and grain crops,soybean widely distributed all over the world.Because single soybean variety adapt to a narrow range of latitudes,various types of varieties were required to suit different ecological conditions.Therefore,it is important topic to reasonably classify these varieties into different groups so as to increase their use efficiency.Classification of soybean based on character of growth period is the main method.Maturity group(MG)suggested by American is a similar method and becomes an international standard because of accuracy and convenient operation.The sowing dates is various among producing areas in China.Domestic scholars have determined a lot of soybean regionalization research and describe relative maturity on a local basis,but it has not been successful in describing relative maturity over different sowing date.However,with the frequent international exchange,it is of vital importance to establish a common method not only can describe the feature of the distribution of soybean varieties in China but also connect to international general standard.Along with the development of molecular biology,a more stable soybean growth period classification standard may be build depending on the genes regulating soybean maturity.